A good horror film that will mess with the mind?

I'm a 15 yr old girl. I don't get scared easily, I've watched tons of scary movies and I actually laugh at some parts.I don't something with a lot of gory in it, that will make it funny to me. And I don't want some stupid teenager movie like the remake (I haven't watched the original) of Nightmare on Elm Street of something similar. I want a really good horror film that will mess with my mind and make me have trouble sleeping.